package com.lxb;

import java.util.HashMap;

public class IsUnique {
    public static void main(String[] args) {

        String s= "leet";
        boolean flag = true;
        HashMap<String,Integer> hash = new HashMap<String,Integer>();
        for (int i=0;i<s.length();i++){
            if(hash.containsKey(s.charAt(i)+"")){
                hash.remove(hash.get(i));
                flag = false;
            }else{
                hash.put(s.charAt(i)+"",1);
            }
        }

        System.out.println(s.toCharArray());

    }
}
